uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

nixos/modules/virtualisation/hyperv-guest.nix

@@ -0,0 +1,66 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.virtualisation.hypervGuest;
+
+in {
+  options = {
+    virtualisation.hypervGuest = {
+      enable = mkEnableOption "Hyper-V Guest Support";
+
+      videoMode = mkOption {
+        type = types.str;
+        default = "1152x864";
+        example = "1024x768";
+        description = ''
+          Resolution at which to initialize the video adapter.
+
+          Supports screen resolution up to Full HD 1920x1080 with 32 bit color
+          on Windows Server 2012, and 1600x1200 with 16 bit color on Windows
+          Server 2008 R2 or earlier.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    boot = {
+      initrd.kernelModules = [
+        "hv_balloon" "hv_netvsc" "hv_storvsc" "hv_utils" "hv_vmbus"
+      ];
+
+      initrd.availableKernelModules = [ "hyperv_keyboard" ];
+
+      kernelParams = [
+        "video=hyperv_fb:${cfg.videoMode}" "elevator=noop"
+      ];
+    };
+
+    environment.systemPackages = [ config.boot.kernelPackages.hyperv-daemons.bin ];
+
+    # enable hotadding cpu/memory
+    services.udev.packages = lib.singleton (pkgs.writeTextFile {
+      name = "hyperv-cpu-and-memory-hotadd-udev-rules";
+      destination = "/etc/udev/rules.d/99-hyperv-cpu-and-memory-hotadd.rules";
+      text = ''
+        # Memory hotadd
+        SUBSYSTEM=="memory", ACTION=="add", DEVPATH=="/devices/system/memory/memory[0-9]*", TEST=="state", ATTR{state}="online"
+
+        # CPU hotadd
+        SUBSYSTEM=="cpu", ACTION=="add", DEVPATH=="/devices/system/cpu/cpu[0-9]*", TEST=="online", ATTR{online}="1"
+      '';
+    });
+
+    systemd = {
+      packages = [ config.boot.kernelPackages.hyperv-daemons.lib ];
+
+      services.hv-vss.unitConfig.ConditionPathExists = [ "/dev/vmbus/hv_vss" ];
+
+      targets.hyperv-daemons = {
+        wantedBy = [ "multi-user.target" ];
+      };
+    };
+  };
+}